2008 17th IEEE International Symposium on the Applications of Ferroelectrics最新文献_第9页

Size effect in metal/ferroelectric/metal heterostructures:Depolarizing effect vs. short-range coupling 金属/铁电/金属异质结构中的尺寸效应:去极化效应与短程耦合

2008 17th IEEE International Symposium on the Applications of Ferroelectrics Pub Date : 2008-12-02 DOI: 10.1109/ISAF.2008.4693765

A. Tagantsev, G. Gerra, N. Setter

{"title":"Size effect in metal/ferroelectric/metal heterostructures:Depolarizing effect vs. short-range coupling","authors":"A. Tagantsev, G. Gerra, N. Setter","doi":"10.1109/ISAF.2008.4693765","DOIUrl":"https://doi.org/10.1109/ISAF.2008.4693765","url":null,"abstract":"Phase transitions in condensed matter are affected by a small volume and/or restricted geometry of the systems. The understanding of the relevant size effects is of practical importance when such systems are used as functional materials in the form of small particles and thin films. At the origin of these effects, one can distinguish two contributions. One is due to the fact that the atoms of the material close to its surface have an environment that is different form that of the bulk atoms. Here, short-range inter-atomic interactions are involved. The other contribution is related to the long-range macroscopic fields (electric, elastic, or magnetic) appearing in particles or films of the material due to its contact with other materials. Proper understanding of the size effect in solid-state systems implies separation of these contributions. In the present paper, we address the problem of this separation in the case of metal/ferroelectric/metal heterostructures, the systems where the long-range contribution is associated with the electrostatic depolarizing field. The problem is treated using an approach developed by the author [1], which combines first principles calculations with the phenomenological theory. The aforementioned contributions to the size effect are evaluated for SrRuO3/BaTiO3/SrRuO3 heterostructures with different (RuO2 orTiO2) terminations of the ferroelectric. It is shown that the relation between these contributions is controlled by the Ç¿¿polarization softnessÇ¿¿ of the metal.","PeriodicalId":228914,"journal":{"name":"2008 17th IEEE International Symposium on the Applications of Ferroelectrics","volume":"44-46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132207444","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Production manufacturing of PZT-based devices: Plasma etch process optimization and results for PZT used as a ferroelectric, as a High k dielectric, and as a piezoelectric material PZT基器件的生产制造:PZT作为铁电材料、高k介电材料和压电材料的等离子蚀刻工艺优化和结果

2008 17th IEEE International Symposium on the Applications of Ferroelectrics Pub Date : 2008-12-02 DOI: 10.1109/ISAF.2008.4693964

P. Werbaneth

{"title":"Production manufacturing of PZT-based devices: Plasma etch process optimization and results for PZT used as a ferroelectric, as a High k dielectric, and as a piezoelectric material","authors":"P. Werbaneth","doi":"10.1109/ISAF.2008.4693964","DOIUrl":"https://doi.org/10.1109/ISAF.2008.4693964","url":null,"abstract":"PZT is used in commercial microfabrication applications for three different families of devices that each rely on one of PZT¿s several useful properties, either as a ferroelectric material, as a High k dielectric material, or as a piezoelectric material. PZT, as a ferroelectric material, is widely deployed in FRAM non-volatile memory applications; PZT, as a High k material, is being used to produce integrated passive and active devices for the cell phone handset market; and PZT, as a piezoelectric material, is employed in transducer applications, such as medical ultrasound imaging. The plasma etch processes used to pattern PZT films for each of these three applications have been optimized for the given requirements of the target application. This paper covers important aspects of each of these three PZT plasma etch applications: optimizing wafer temperature during etching for fine-feature FRAM fabrication, optimizing process and tool robustness in ¿copy exactly¿ plasma etching for passive device manufacturing, and optimizing plasma etch processes for piezoelectric PZT applications with film thicknesses of tens of microns.","PeriodicalId":228914,"journal":{"name":"2008 17th IEEE International Symposium on the Applications of Ferroelectrics","volume":"107 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133952934","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Full set of complex material constants for porous piezoelectric ceramics 多孔压电陶瓷的全套复材料常数

2008 17th IEEE International Symposium on the Applications of Ferroelectrics Pub Date : 2008-12-02 DOI: 10.1109/ISAF.2008.4693810

Andrey Rybianets, Anastasia Rybianets, A. Nasedkin

{"title":"Full set of complex material constants for porous piezoelectric ceramics","authors":"Andrey Rybianets, Anastasia Rybianets, A. Nasedkin","doi":"10.1109/ISAF.2008.4693810","DOIUrl":"https://doi.org/10.1109/ISAF.2008.4693810","url":null,"abstract":"Porous piezoelectric ceramics are important for a variety of applications such as medical ultrasonic devices, non-destructive testing, underwater acoustics etc. In this paper a line of proprietary porous piezoelectric ceramics with 3-0/3-3 connectivity types were systematically studied. Complex sets of elastic, dielectric and piezoelectric coefficients of the porous piezoelectric ceramics were measured by ultrasonic and impedance spectroscopy methods using Piezoelectric Resonance Analysis (PRAP) software. Special attention was paid to the microstructure/properties interrelation and accurate determination of low-Q porous piezoelectric ceramics parameters including losses and dispersion. It was shown, that at any connectivity type and porosity up to 70 % the real structures of porous piezoelectric ceramics are close to the matrix medium structure with continuous piezoelectric ceramic skeleton. Finite element modeling of effective constants of the porous piezoelectric ceramics was performed using ANSYS software package. Critical comparison of numerical FEM calculations with the results of various approximated formulas, unit cell models and experimental data for different porous piezoelectric ceramics was carried out. Microstructural and physical mechanisms of losses in porous piezoelectric ceramics, as well as technological aspects of its large-scale manufacture and application in ultrasonic transducers were considered. A line of high-performance HIFU, NDT and medical diagnostics ultrasonic transducers made from porous piezoelectric ceramics was manufactured and tested.","PeriodicalId":228914,"journal":{"name":"2008 17th IEEE International Symposium on the Applications of Ferroelectrics","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133328972","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Multiple exciton generation in semiconductor quantum dots and novel molecules: Applications to third generation solar photon conversion: 半导体量子点中多激子的产生及新分子:在第三代太阳光子转换中的应用

2008 17th IEEE International Symposium on the Applications of Ferroelectrics Pub Date : 2008-12-02 DOI: 10.1109/ISAF.2008.4693953

A. Nozik

引用次数: 2

Time-resolved characterization of domain switching in ferroelectrics using X-ray and neutron diffraction 用x射线和中子衍射表征铁电体的畴转换

2008 17th IEEE International Symposium on the Applications of Ferroelectrics Pub Date : 2008-12-02 DOI: 10.1109/ISAF.2008.4693913

J. Jones, A. Pramanick, J. Daniels

引用次数: 0

Band gap energy of perovskite structured ABO3 compounds 钙钛矿结构ABO3化合物的带隙能

2008 17th IEEE International Symposium on the Applications of Ferroelectrics Pub Date : 2008-12-02 DOI: 10.1109/ISAF.2008.4693923

Soonil Lee, W. Woodford, C. Randall

{"title":"Band gap energy of perovskite structured ABO3 compounds","authors":"Soonil Lee, W. Woodford, C. Randall","doi":"10.1109/ISAF.2008.4693923","DOIUrl":"https://doi.org/10.1109/ISAF.2008.4693923","url":null,"abstract":"Band gap energy for nonstoichiometric BaTiO3 and perovskite structured ABO3 compounds have been investigated in regard to the relationship among band gap energy, defect chemistry, and crystal structure. The band gap energy was determined by UV-Visible spectrophotometer for powder samples, which are synthesized by citrate process and ultrasonic mixing to avoid the impurity effects. The band gap energy of nonstoichiometric BaTiO3 varied systematically in the solubility region around stoichiometric BaTiO3, indicating that the partial Schottky defects affect to the band gap energy. The band gap energy for ABO3 compound had systematic trends with each parameter such as ionic size, lattice size, B-O bonding distance, tolerance factor, etc. Lattice volume and tolerance factor showed a single trend with band gap energy, but unlike simple binary compounds, the band gap energy for ABO3 compounds had a complex trend with the bonding distance. In addition to the simple ABO3 compounds, in the solid solution system for two different end members of ABO3 compounds, the lattice tilt effect on band gap energy will be discussed. This study provides an insight in understanding the origin of band gap energy and engineering the band gap energy.","PeriodicalId":228914,"journal":{"name":"2008 17th IEEE International Symposium on the Applications of Ferroelectrics","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123907400","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The dependence of optical and electrical properties of GaN nanowires on the growth temperature Paper #NA003 GaN纳米线的光学和电学性质与生长温度的关系

2008 17th IEEE International Symposium on the Applications of Ferroelectrics Pub Date : 2008-12-02 DOI: 10.1109/ISAF.2008.4693793

A. Talin, George T. Wang, E. Lai, R. Anderson

引用次数: 0

Role of potassium content in sodium bismuth titanate piezoelectrics for higher temperature applications. 高温钛酸铋钠压电材料中钾含量的作用。

2008 17th IEEE International Symposium on the Applications of Ferroelectrics Pub Date : 2008-12-02 DOI: 10.1109/ISAF.2008.4693815

J. F. Carroll, D. Payne, Y. Noguchi, M. Miyayama

引用次数: 0

Secrets of PZT PZT的秘密

2008 17th IEEE International Symposium on the Applications of Ferroelectrics Pub Date : 2008-12-02 DOI: 10.1109/ISAF.2008.4693841

Dragan Damjanovic

{"title":"Secrets of PZT","authors":"Dragan Damjanovic","doi":"10.1109/ISAF.2008.4693841","DOIUrl":"https://doi.org/10.1109/ISAF.2008.4693841","url":null,"abstract":"Lead zirconate titanate, Pb(Zr,Ti)O3 or PZT, is the best known and most important piezoelectric material. During the fifty years since its discovery its structure and properties have been studied in a great detail. Despite these efforts and the fact that PZT is used in innumerable devices its properties are still not well understood. PZT is not (widely) available in form of sufficiently large single crystals and its lattice properties are therefore inaccessible experimentally. PZT¿s phase diagram has undergone a major modification a decade ago when a monoclinic phase was discovered in the morphotropic phase boundary region; this modification and the nature of the apparent monoclinic signature are now being a subject of intense debate. PZT is never used chemically pure in applications and its main modifications are in form of acceptor (hard) and donor (soft) doped materials. Our understanding of details of hardening and softening processes is, however, insufficient as demonstrated by recent studies of defect chemistry of hard and soft materials, showing a more complex defect structure than previously thought. In this presentation we shall review the recent advances in revealing the remaining secrets of PZT: the presence of the monoclinic phase, the nature of the morphotropic phase boundary, mechanisms and defects involved in hardening and softening, balance between domain wall and lattice contributions to the outstanding properties of PZT will be discussed.","PeriodicalId":228914,"journal":{"name":"2008 17th IEEE International Symposium on the Applications of Ferroelectrics","volume":"72 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132336222","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

MU016- deposition methods of BiFeO3 thin films BiFeO3薄膜的沉积方法

2008 17th IEEE International Symposium on the Applications of Ferroelectrics Pub Date : 2008-12-02 DOI: 10.1109/ISAF.2008.4693788

M. D. Casper, M. Losego, S. Aygun, J. Maria

{"title":"MU016- deposition methods of BiFeO3 thin films","authors":"M. D. Casper, M. Losego, S. Aygun, J. Maria","doi":"10.1109/ISAF.2008.4693788","DOIUrl":"https://doi.org/10.1109/ISAF.2008.4693788","url":null,"abstract":"Bismuth iron oxide (BiFeO3 or BFO) is a particularly interesting multiferroic perovskite with ferroelectric and antiferromagnetic transition temperatures significantly above room temperature. In this work, BiFeO3 films are synthesized by a chemical solution deposition (CSD) sol-gel process on platinized silicon substrates and by physical vapor deposition (PVD) through RF-sputtering on iridium-sapphire substrates. The crystallization behavior and phase assemblage of these films was examined by X-ray diffraction (XRD). Analysis of CSD-prepared films revealed that a 0.25 M solution with 5% excess bismuth annealed at 550 °C in air produced polycrystalline films with the lowest occurrence of non-perovskite Bismuth iron oxide phases. For films made by PVD, the absence of oxygen during sputtering was found to enhance phase purity, and using a target with 7% excess bismuth allowed phase-pure films to be prepared at 600 °C. Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM) were used to investigate the microstructure of the BiFeO3 films. Porosity was found to be a significant problem in CSD-prepared films that were dried on a hotplate at 300 °C before annealing. Lowering the temperature of this drying step or omitting it was found to decrease root-mean-square (rms) surface roughness. The microstructure of the sputtered films was found to be dense, uniform, and crack-free a surface roughness of to 16 nm for BiFeO3 sputtered at 600 °C.","PeriodicalId":228914,"journal":{"name":"2008 17th IEEE International Symposium on the Applications of Ferroelectrics","volume":"72 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130836656","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0